Railway signal apparatus.



No. 643,498. Patented Feb. I3, |900.

C. R. GURR &. H. TMLINS.

RAILWAY SIGNAL APPARATUS.

(Application led Sept. 21, 1899.)

(No Model.)

l@ )m f me mms PETERS co. Pno'roLl-wo.. wAsnmaYoN. n. c.

NITED STATES PATENT OFFICE.

' CHARLES R. GURR AND HERBERT TOMLINS, OF LONDON, ENGLAND.

RAILWAY SIGNAL APPARATUS.

SPECIFICATION forming part of Letters Patent No. 643,498, dated February 13, 1900.

- I Application led September 21, 1899. Serial No. 731,174. (No'model.) Y

T0 a/ZZ whom t mayconcern.-

Be it known that We, CHARLES RICHAR GURR, builder and contractor, al resident of 30 Cranbrook road, Chiswick, and HERBERT TOMLINs,engineer, aresident of 5l Cambridge road, Hammersmith, London, W., England, have invented new and useful Improvements in Railway Signal Apparatus, of which the following is a full, clear, and exact description.

This invention relates to railway-signal--operating mechanism, and has for its object to compensate for variation of length of the wire connections through which the signals are operated and to render impossible the partial or imperfect operation of the signals due t0 such variation. With this object the wire connections are kept under constant tension and are at all times free to expand or contract, being normally disconnected from the hand-levers by which the signals are operated, the coupling up of a hand-lever with the corresponding connecting-wire being automatically effected at the moment when the signal is to be lowered and the connections between the wire and the lever ceasing immediately the signal is returned to danger.

Reference is to be had to the accompanying drawings, forming part of this speciication, wherein-'- Figure l is a general View of a signal and of the cabin containing the lever by which it is operated. Fig. 2 is a part-sectional sideelevation of the coupling device. Figs. 3, 4, and 5 show a set of three in different positions, Fig. 3 being an end View, and Figs. 4 and 5 sections on line 4 5, Fig. 2, respectively, showing the device in and out of engagement. Fig. Gis a part-sectional side elevation of a lnodied construction of the coupling device, the operation being, however, the same in the case of both forms of construction.

The same letters otreference denote like parts in all the tigures.

Referring to Figs. l to 5, A is the hand-lever in the signal-cabin, and S the signal to be operated in the usual manner-that is to say, the signal is normally held at danger by a counterweight B, except when pulled down by the hand-lever, this lever acting through the connecting-wire C, to which, however, the lever is only temporarily coupled through the medium of the coupling device to the free rack-like member D, with which the wire C is connected. This wire is con= stantly strained by a Weight E, which, acting in opposition to weight B, necessitates the latter being made so much the heavier.

F is the guide-frame of the coupling device, on which a carriage Gis tted to run, said carriage being formed of two cheek-plates provided with friction-rollers g, embracing the guide-frame and also the rack-bar D,which are arranged parallel, the one above the other. The lower arm of the hand-lever A is connected by a link H with the carriage G through the medium of a cross-pin I, on which are mounted rollers J, that work in inclined cam-slots K in the side cheeks of the carriage C. The inclination of the cam-slots corresponds to that of the ratchet-shaped teeth of the rack-bar D, so that immediately the link I-I is pulled a downwardly-projecting spur L on the head of the link is caused to enter into positive engagement with the rack-bar D. This hap'- pens at the very commencement of the move-- ment of the hand-lever A, so that by the continued movement of the latter the motion will be transmitted to rack D and wire C and the signal will be pulled oft. On the reverse movement of the hand-lever the signal will first be raised to danger, and the connection of the hand-lever with the connectingwire C will then be severed.

The rack is of sufficient length to insure the making of the necessary connection under all possible variations of length of the wire C. The rollers g of the carriage permit free longitudinal sliding movement of the rack-bar D to accommodate the variations of length of the wire C, while they maintain it against any tendency to sag and insure a secure connection of the spur with the rack.

The construction shown in Fig. 6 only differs from the others -in that the relative positions of the fixed guide F and rack-bar D are between them, the action being precisely similar in all respects.

Although it is obvious that the horizontal IOO direction of working is preferable, it is not obligatory.

In the working of this apparatus it will be apparent that should the wire C undergo a considerable variation of length in the interval between two operations of the signal which it controls this diierence of length will be taken up or allowed for by the weight E, and consequently the spur L on rengaging with the rack D will not engage the same tooth as on the previous occasion.

Having now particularly described and ascertained the nature ofthe said invention and in what manner the same is to be performed, we declare that what we claim is l. rlhe combination with a signal-operating wire under tension and a rack connected to the wire, of a carriage supporting said rack and through which said rack is slidable, Said carriage being formed with an inclined slot, a link fitted in said slot and formed with a spur adapted t0 engage the teeth of the rack when the link moves down in said slot, and means for moving' said link, as specified.

2. The herein-described means of allowing and compensating for Variations of length of a signal-operating wire, which consists in the combination with a signal-wire, normally disconnected from its operating hand-lever and under a constant tension, of an automatic connecting and disconnecting .device interposed between the hand-lever and the wire, and consisting of two normally-disconnected members adapted to be thrown into connection by the action of cams at the initial movement of the operating hand-lever, the one member being a rack connected to the wire and the other a spur connected to the handlever rod and combined with cam-slots in a sliding carriage which have for effect t0 throw the spur into or out of engagement with the rack and to maintain such condition of engagement and disengagement, substantially as specified.

3. The combination with asignal-operating wire held under tension and a rack connected to said wire, of a guide-frame, a carriage having rollers by which it is mounted to move in said frame, and otherl rollers on which the rack is movable, said carriage being further provided with inclined slots, a link whose head is provided with rollers movable in said slots, and a spur adapted to engage with the rack, and means for moving said link, as specified.

CHARLES R. GURR.' HERBERT TOMLTNS. In presence ofw- C. G. CLARK, T. W. KENNARD. 

